Fuel usage ???? bad ????

[Heylin]

AnNother fill yesterday, all town driving, worked out to 17.1L per 100

Theme seems to be a pattern (watching the avg kms per litre in computer), when cold it basically gets pinned at 5.9kms per litre).

After warm up and driving around a bit it start creeping up slowly ie 6.0, 6.1, but then quickly loses any gains when you start up the next morning.

Filled the car from warm and went for a drive and after 10 kms of warm driving im upto 6.5kms per litre and climbing.

Wondering if the warmup routine is a bit rich ?

Also how long should the car take to warm up ? and how far up the temp gauge should the needle be ?

[paulngui]

Mine warms up more or less just as I get to work, which is 4 kms/10 mins from home. And that's half way up the temp gauge.

[KwS]

Shit, i'd get a scooter or something if i only lived 4 ks from work... wouldnt bother driving!

[clintondane]

Mate, something is seriously wrong with those figures. Even 6.5ks per litre is crap. Almost 16 litres per 100 ks is worse than an hsv Holden would use. I don't know what to suggest but having read the thread, its gotta be the tune. Hope you get it sorted soon.

[Heylin]

 clintondane said:

Mate, something is seriously wrong with those figures. Even 6.5ks per litre is crap. Almost 16 litres per 100 ks is worse than an hsv Holden would use. I don't know what to suggest but having read the thread, its gotta be the tune. Hope you get it sorted soon.

The fact that it loses a fair bit of average economy during the warmup period would suggest the warmup is possibly a bit on the heavy side.

My old MR2 on a super rich tune ran about 18L per 100 kms for town driving. So I suspect it is running quite rich when cold.

[clintondane]

Quite rich, understatement much? Lol.

[Heylin]

 clintondane said:

Quite rich, understatement much? Lol.

Only done 39km since the weekend, and its now showing 20L per 100km average (5kms per litre on the computer).

[Stoffa]

Now my car is a daily driver i've got some numbers, brand new forged engine running 14psi on a modified VF turbo with a basic road tune and I'm getting about 12.5L/100km (400km per tank) not too bad I guess.

Thats a 65km round trip to work and back 75% motorway driving with no traffic.

[Guest]

Sounds highish Im getting 10ish per 100km mixed road driving and Im totally untuned and the set up is completely different modwise. TD04 to VF23 up grade, front mount, flipped and twisted.

I think I use a shitload of gas driving with a cold car though coz my going to work every morning adds up pretty quick.

[Heylin]

Reckon we need a thread where people can modify their posts in the following format

Car (Make, model, year)

mods

Fuel type (95, 98)

L per 100km - KmsTown\KmsHighway

eg

14.2 | 150 | 250

17.1 | 330 | 0

10.5 | 10 | 450

[Pappu1]

i have been getting 9km/litre form v7 on 80% city and 20% open road driving (450km for 50 litres)

will be modifying the fueling maps and see where i get to

careful driving with not much boost thrown in

[Heylin]

Sitting in Tauranga at the moment, filled up before leaving Hamilton, and computer is showing average of 11-12km per L all the way down.

So looking like it will get 9-10L per 100km for open road driving, which incidently is the best we have ever got, so the tune has definately improved the open road economy.

Prior to tuning we were getting 11L per 100km for the same trip.

Definately something up with warmup and\or acel enrichement.

[Guest]

Do you warm your car up prior to driving? Ive found it makes a fuckin big difference.

[Heylin]

 evowrx said:

Do you warm your car up prior to driving? Ive found it makes a botherin big difference.

I stay off the turbo until its fully warmed up, but I always thought the best way to warm up was to drive normally, rather than idling it in garage.

[Guest]

Thrashing temp and warming up the engine are a bit different. My car runs lumpy as bother till it warms up and uses a s***load of gas under load. If I warm it up for 2-3 minutes its fine then warm it up while driving before hitting the loud pedal too hard. YMMV Im 1999 v5.

[Heylin]

Filled up on the way home, actual usage for the return trip was 8.6L per 100km. Quite impressed. So it uses 2 times more for town driving.

[Heylin]

Now this is interesting, warmed up town driving is 13.3L per 100 kms

So based on my average of 17.3L and my cold vs warm kms, I worked out that cold running is using 38L per 100 kms. (based on 1.5km to reach operating temp).

So the working week return trip to and from home is using nearly 1/3 of the tank for only 20% of the total kms travelled.

I thought cold driving used 20% more than warmed up driving ?, mine seems to be a 100% more. Based on the 20% it would be putting me in the 14-15L per 100 which is what id expect for city driving.